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"Causes" of diabetes

End the myths & misinformation

Despite popular belief, diabetes is not caused by eating too much sugar and people don’t “give themselves” diabetes. Popular media often depicts disease and people with diabetes in an inaccurate and harmful light.

There are several different reasons why someone may develop diabetes. The cause of diabetes depends on your genes, family history, ethnic background, and other factors such as the environment and your health. It also depends on the type of diabetes you have.

There is no common cause that fits every type of diabetes. The reason why someone will develop type 1 diabetes is very different from the reasons why another person will develop type 2 diabetes.

Type 1 diabetes

Type 1 diabetes is called an autoimmune disease, because the body’s system for fighting infection, your immune system, attacks and destroys the cells in your pancreas that make insulin. As a result, the body is left without insulin.

Researchers think that your genes or the environment may be responsible for triggering type 1 diabetes. TrialNet is a study that is working to determine the causes of type 1 diabetes and possible ways to prevent it.

Type 2 diabetes

Type 2 diabetes is much more common than type 1 diabetes. Type 2 diabetes is caused by several factors including obesity, ethnic background, a family history of type 2 diabetes and other environmental factors.

You are more likely to develop type 2 diabetes if you are not physically active and are overweight or obese.

Type 2 diabetes is the result of not enough insulin being made in the pancreas, and insulin resistance when the body isn’t able to use the insulin it makes. When this happens, glucose (sugar) in your blood is not able to enter the cells where it should get used for energy.

Assess your risk

Think you or someone you love is at risk of having diabetes? Take the CANRISK test to know your risk.

Gestational diabetes

Gestational diabetes occurs during pregnancy and is caused by the hormone changes of pregnancy. A woman’s genes, diet and exercise habits may also be responsible. In gestational diabetes, the pancreas can’t make enough insulin.

Like type 2 diabetes, women who are overweight or obese may already have insulin resistance when they become pregnant. Having a family history of diabetes makes it more likely that a woman will develop gestational diabetes.

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